(The interaction of ferredoxin:NADP sup + oxidoreductase and ferredoxin:thioredoxin reductase with substrates)

Technical Report · Wed Jan 01 04:00:00 EST 1992

DOI:https://doi.org/10.2172/7085813· OSTI ID:7085813

We seek to map the ferredoxin-binding sites on three soluble enzymes located in spinach chloroplasts which utilize ferredoxin as an electron donor:Ferredoxin:NADP{sup +}oxidoreductase (FNR); ferredoxin:thioredoxin reductase (FTR) and glutamate synthase. As the availability of amino acid sequences for the enzymes are important in such studies, that the amino acid sequence of glutamate synthase needs be determined, the amino acid sequences of FNR, FTR and ferredoxin are already known. Related to an aim elucidate the binding sites for ferredoxin to determine whether there is a common binding site on all of these ferredoxin-dependent chloroplast enzymes and, if so, to map it. Additionally thioredoxin binding by FTR needs be determine to resolve whether the same site on FTR is involved in binding both ferredoxin and thioredoxin. Considerable progress is reported on the prosthetic groups of glutamate synthase, in establishing the role of arginine and lysine residues in ferredoxin binding by, ferredoxin:nitrite oxidoreductase nitrite reductase, labelling carboxyl groups on ferredoxin with taurine and labelling lysine residues biotinylation, and low potential heme proteins have been isolated and characterized from a non-photosynthetic plant tissue. Although the monoclonal antibodies raised against FNR turned out not to be useful for mapping the FNR/ferredoxin or FNR/NADPinteraction domains, good progress has been made on mapping the FNR/ferredoxin interaction domains by an alternative technique. The techniques developed for differential chemical modification of these two proteins - taurine modification of aspartate and glutamate residues and biotin modification of lysine residues - should be useful for mapping the interaction domains of many proteins that associate through electrostatic interactions.

• Research Organization: Texas Tech Univ., Lubbock, TX (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG05-90ER20017
• OSTI ID: 7085813
• Report Number(s): DOE/ER/20017-1; ON: DE92040339
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ANTIBODIES
BIOASSAY
BIOCHEMICAL REACTION KINETICS
COENZYMES
DNA SEQUENCING
DOCUMENT TYPES
ENZYMES
FERREDOXIN
FOOD
IMMUNOASSAY
ISOENZYMES
KINETICS
LEGUMINOSAE
MAGNOLIOPHYTA
MAGNOLIOPSIDA
METALLOPROTEINS
MOLECULAR STRUCTURE
MONOCLONAL ANTIBODIES
NITRO-GROUP DEHYDROGENASES
NITROREDUCTASES
NUCLEOTIDE DEHYDROGENASES
ORGANIC COMPOUNDS
OXIDOREDUCTASES
PHASEOLUS
PLANTS
PROGRESS REPORT
PROTEINS
REACTION KINETICS
SPECTROSCOPY
SPINACH
STRUCTURAL CHEMICAL ANALYSIS
VEGETABLES